Chain joint seal

Abstract

A preferred embodiment of the invention described herein includes a method and apparatus for providing a seal between at least the outer sidebar and pin bushing of a chain link assembly. The apparatus includes a seal having an outer collar and an inner resilient ring, the outer collar preferably having a mating ridge and the resilient ring being molded onto the collar. This seal also includes outer ribs for providing a sealed contact against the outer sidebar, and may include inner ribs. The seal is part of a chain link assembly positioned between the outer and inner sidebars and surrounding a pin bushing end. A fluid (e.g., grease) may be advantageously placed between the ribs, lubricating the rib—sidebar interface and thereby reducing wear of the ribs.

1. A seal for limiting wear in a chain link assembly, the chain link assembly having alternating pairs of inner and outer spaced-apart sidebars joined by pin assemblies that include a bushing, the seal comprising:
 a wear-resistant collar having an inner circumferential surface including a first substantially flat portion and at least one of the group of a mating protrusion and mating indentation; 
 a resilient member positioned radially inward of the collar, comprising
 an outer circumferential surface shaped to engage the inner circumferential surface of the collar, 
 an axially extending outer side having a first protrusion thereon and an axial thickness greater than the axial thickness of the collar, for forming a sealing contact against an outer sidebar, and 
 an inner circumferential surface for forming a sealing contact with a bushing. 
 
 
   
   
     2. The seal of  claim 1 , wherein the collar comprises a metal, and the resilient member is in molded contact with the collar, whereby the outer circumferential surface substantially conforms to the inner circumferential surface of the collar. 
   
   
     3. The seal of  claim 1 , wherein the first protrusion of the resilient member comprises two spaced apart ribs defining a pocket between the ribs. 
   
   
     4. The seal of  claim 1 , further comprising a radially extending inner side having a second protrusion thereon for forming a sealing contact against an inner sidebar. 
   
   
     5. The seal of  claim 4 , wherein the collar has radially extending inner and outer sides, and the first and second protrusions both extend radially outwardly over a portion of the inner and outer sides of the collar. 
   
   
     6. The seal of  claim 4 , wherein the first protrusion of the resilient member comprises spaced apart first ribs defining a pocket between the ribs, and second protrusion of the resilient member comprises spaced apart second ribs defining a pocket between the ribs. 
   
   
     7. The seal of  claim 6 , wherein at least one pocket of the first and second ribs are at least partially filled with lubricant. 
   
   
     8. An apparatus including a chain link assembly comprising:
 alternating pairs of inner and outer spaced-apart sidebars joined by pin assemblies that include respective bushings; 
 first and second seals positioned around a bushing of a first pin assembly, the first seal positioned between the first outer sidebar and a first inner sidebar, the second seal positioned between the second outer sidebar and second inner sidebar, each seal comprising: 
 a collar having an inner circumferential surface including a substantially flat surface with at least one of the group of a mating protrusion and mating indentation, an axial thickness; 
 a resilient member positioned radially inwardly of the collar, comprising an outer circumferential surface shaped to engage the inner circumferential surface of the collar, 
 an axially extending first side having a first protrusion thereon and an axial thickness greater than the axial thickness of the collar, and an inner circumferential surface for forming a sealing contact with the bushing, and a second protrusion on a radially extending second side radially outward the first side; 
 wherein the first protrusion of each of the first and second seals, respectively, sealingly contact the first and second outer sidebars, respectively. 
 
   
   
     9. The apparatus of  claim 8 , wherein the first protrusion of the first seal sealingly contacts the first outer sidebar. 
   
   
     10. The apparatus of  claim 9 , wherein the pin assembly further comprises a pin extending through the outer sidebars, and wherein the bushing surrounds the pin between the outer sidebars, and wherein the first protrusion of the first seal comprises plural spaced apart ribs defining a pocket between the ribs. 
   
   
     11. The apparatus of  claim 9 , wherein the collar is a metal, and the resilient member is molded to the collar, whereby the outer circumferential surface complimentarily matches the inner circumferential surface of the collar, and the first and second protrusion of the resilient member comprises plural spaced apart ribs defining a pocket between the ribs, the ribs of the first and second protrusions being compressed against the outer and inner sidebars, respectively. 
   
   
     12. The apparatus of  claim 11 , wherein at least one pocket is at least partially filled with lubricant so the ribs are lubricated during operation of the assembly. 
   
   
     13. The apparatus of  claim 8 , wherein the collar of the first seal has radially extending inner and outer sides, and the first and second protrusions extend radially outwardly over a portion of the inner and outer sides of the collar.